Thankyou for your question.
Please let me know your city,state,country so I am sure to find the right help for you.
Thankyou for your reply.
River Otters usually have their kits about this time of year and will often move on after the kits are born.
Attempts to drive the mother away could result in babies dying under your trailer so you may want to be sure that's not the situation that would only add to the problem.
Kits are not ready to leave the den until they are about 3-4 months old.
I am offering you some options below to help with the smell you have currently.
To start with you'll need to somehow rake under the trailer to remove whatever you can. (wear a mask so you're not overcome) If you don't remove the source of the smell then it will return . Otters leave behind things like fish parts,etc.and Otters tend to have certain places that are used solely for toilets.This could be a part of the smell.
Using regular household bleach /water with a spray bottle would be tedious and a carefully used pressure washer might help after you've raked out as much as you can.
It's difficult to do I know and you may need to ask someone to help .
There is a product sold specifically to help kill the odor and it's here:
http://www.wildlifecontrolproducts.com/cgi-bin/ez-catalog/cat_display.cgi?account=X355889;search=2;search=Animal%20repellents%2C%20Animal%20removal;limit=category;v=2.0 (Scroll down to "One Shot Deodorizer")
I think I would also use a sonic pest repeller year round or coyote urine and you'll find that at the website above also to keep the rascals away.
Using a fence that measures 3 x 3 (7.6 cm x 7.6 cm) or smaller wire mesh before you replace the siding can help prevent them from returning .Hog wire type fencing can be used but otters can enter through it by making the bottom wire larger,so you'd have to check that type more often.
The office listed below is for The Conservation Commission who may have help to offer you concerning your problem.
Vancouver Island Regional Office #3 - 1200 Princess Royal AvenueNanaimo, BC V9S 3Z7 Phone:(NNN) NNN-NNNNFax:(NNN) NNN-NNNNnanaimo@bccf.com
I have to agree with Don about calling your local office there for help with removal but also it depends on your water source as to how strong the bleach will be. A pressure washer would work you just have to use more then 2 parts water to one part bleach and you have to make sure and wear a mask as the fumes will be quite strong. You just have to use less water strength and more bleach and this will allow tyou to place a good cover into the ground underneath your home. The only other way is with a fogger type killer but then that would only work while they were under there at the time. And I do agree with Don that it would be better to call the Conservative Commission as they are able to deal with these issues and have the proper tools to remove them safely as the key is to remove and not kill especially the babies and they can do this for you. The site Don gave you will help with the odor that you are having such issues with now and once they can be removed using skirting or wiring can help to prevent any furture problems. I am just offering my help with your situation so there is no way for you to accept my offer, he has sent word to other experts as well who may be able to also offer some other possible solutions as well but please for me accept his answer as it is wonderful advice and I am just adding a little to your response to him is all. I do wish you luck and if any other pet expert has more to add they will see this when they log in. Best of luck to you!!
Hello, thanks for letting me know. Glad you could get some relief but in case it does not clear them out totally I hope you contact the following office.They might come and help you free of charge.
Vancouver Island Regional Office #3 - 1200 Princess Royal AvenueNanaimo, BC V9S 3Z7 Phone:(NNN) NNN-NNNNFax:(NNN) NNN-NNNNhttp://mailtoXXX@XXXXXX.XXX